But how did April Fools' Day start and why is April Fools' Day on April 1? History.com tells us that while its true origin remains somewhat of a mystery, historians theorize that the tradition dates back to 1582 when France switched from the Julian calendar to the Gregorian calendar as decreed by the Council of Trent.

Some trace the prank day's origins to 1582 after Pope Gregory XIII ordered the adoption of Gregorian calendar which moved New Year's Day from the end of March to Jan. 1.

Those who were slow to adhere to the new calendar became the subject of ridicule and many jokes. They would often become referred to as "poisson d'avril" (or April fish), someone who could be caught and was gullible.

Throughout history there have been some great April Fools' Day pranks:

On April 1, 1878, the New York Graphic ran an announcement that claimed Jersey's own Thomas Edison invented a machine that turned soil to cereal and water into wine. Newspapers nationwide ran with the story.

In 1987, Los Angeles disc jockey Steve Morris announced on KRTH-FM that California highways in Los Angeles and Orange counties would be shut down April 8-May 1 for major roadway repairs. Pandemonium ensued.

In 1996, Taco Bell freaked out the nation when they claimed that they purchased the Liberty Bell and was going to rename it. In 1998, Burger King announced their Left-Handed Whopper.

Google, who has a history of pulling April Fools' jokes, claimed in 2011, that their Gmail Motion would be able to compose a message with simple hand gestures. People completely believed it.

And just two days ago, actor Jon Lovitz and model Jessica Lowndes pulled an elaborate prank when they told everyone that they were engaged. Many media outlets had to run corrections because it was all part of an elaborate April Fools' Day prank.